1. Field of the Disclosure
This disclosure relates generally to drill bits and systems for using same for drilling wellbores.
2. Background of the Art
Oil wells (also referred to as wellbores or boreholes) are drilled with a drill string that includes a tubular member having a drilling assembly (also referred to as the drilling assembly or bottomhole assembly or “BHA”) which includes a drill bit attached to the bottom end thereof. The drill bit is rotated to disintegrate the rock formation to drill the wellbore. The BHA includes devices and sensors for providing information about a variety of parameters relating to the drilling operations (drilling parameters), the behavior of the BHA (BHA parameters) and the formation surrounding the wellbore being drilled (formation parameters). A large number of wellbores are drilled along a contoured trajectory. For example, a single wellbore may include one or more vertical sections, deviated sections and horizontal sections. Some BHAs include adjustable knuckle joints to form a deviated wellbore or elements such as arms or paddles on a rotary steerable drilling system for directional control. Such steering devices are typically disposed on the BHA, i.e., away from the drill bit. However, it is desirable to have steering devices that are close to or on the drill bit to effect steering, improve rate of penetration of the drill bit and/or to extend the drill bit life. Further, it is desirable to have a mechanism on the bit to effect steering that has few components and moving parts to improve reliability and reduce downtime.